This application relates to apparatus and methods for controlling, and/or sensing, the states of multiple components or devices, and has particular application to devices of the types used in or in connection with gaming machines.
In electronic gaming machines, of the type commonly used in gaming establishments, it is desirable to provide devices and techniques for attracting players and providing an entertaining play environment. To this end, gaming machines commonly use light displays, which can be operated in a variety of modes, including an attract mode. For this purpose, a plurality of individual lights, which may number from tens to hundreds for an individual machine, are blinked on and off in predetermined patterns, depending upon the mode of operation of the machine. Such lights may be in the form of light-emitting diodes (LEDs) and may form part of an illuminated switch, which includes a switch mechanism and one or more associated LEDs. Such LEDs may be provided in a variety of colors.
It is possible to connect groups of such devices, e.g., like-colored lights, in parallel in order to reduce the number of wires required for controlling them. However, in order to maximize the number of different display patterns which can be generated, it is desirable to have the devices individually controlled, but this may require a very large number of wires. For example, in the case of LEDs, there would have to be one control wire for each LED and a common wire. In the case of illuminated switches, even more wires would be required. For example, in a machine panel with fourteen illuminated switches, a minimum of thirty wires would be required (switch common, lamp common, fourteen switch control wires and fourteen lamp control wires), and this assumes that there is only one lamp per switch or, if multiple lamps per switch, that all the lamps of a switch are connected in parallel. Accordingly, in machines with large numbers of such devices to be controlled, individual control of the devices becomes impractical.